BRUSSELS—German Chancellor
Angela Merkel
's
cabinet approved the deployment of two batteries of German Patriot air-defense missiles to defend Turkey against possible attacks from Syria, amid indications that Ankara would receive considerably less coverage than it had requested from its North Atlantic Treaty Organization allies.

NATO members are likely to send as few as six Patriot air-defense batteries to Turkey in all, suggesting large parts of the country's border region would be unprotected in case of a strike, according to diplomats and officials.

NATO foreign ministers gave the go-ahead to the deployments on Tuesday following a Turkish request last month, insisting that the Patriots would be used only defensively and not as part of a no-fly zone over Syria.

Earlier

Germany's cabinet approved the deployment of the two batteries and up to 400 troops, pending a final approval by the German parliament between Dec. 12 and 14. The initial mandate will expire on Jan. 31, 2014. The Dutch deployment, also likely to be of two batteries, is expected to receive cabinet approval Friday and obtain subsequent backing from parliament.

Diplomats said the U.S. would likely add a further two batteries to the total. The U.S. Patriot missile capability is in heavy demand in other parts of the Middle East and in Asia.

The total of six batteries is significantly fewer than implied by Turkey's first request. According to one person involved in discussions between Turkey and Germany, Turkey originally sought help to defend all population centers within 50 miles of Turkey's roughly 565-mile border with Syria, implying the need for as many as 15 batteries.

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U.S. State Secretary Clinton at an Organization for Security and Cooperation in Europe meeting in Dublin, where she met Russia's Lavrov.
European Pressphoto Agency

Separately, Secretary of State Hillary Clinton joined Russian Foreign Minister
Sergei Lavrov
for talks that suggested Washington and Moscow could be moving ahead to find a strategy to end the Syrian crisis. The U.S. and Russia have fought bitterly over how to address the conflict.

The two met alone and then for 40 minutes with Lakhdar Brahimi, the U.N. peace envoy to Syria, on the sidelines of a human-rights conference in Dublin to discuss how to support a political transition in practical terms, said a State Department official. But there was no major breakthrough on Syria during the meeting and Washington and Moscow are at the very early stages of trying to forge a common position, a senior U.S. official said.

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A patriot missile is fired during an exercise in 2008 in Crete, Greece.
Getty Images

In Washington, Defense Secretary Leon Panetta said intelligence reports raise fears that an increasingly desperate Syrian President
Bashar al-Assad
is considering using his chemical weapons arsenal, which the U.S. and Russia agree is unacceptable.

"We remain very concerned, very concerned," Mr. Panetta said, according to the Associated Press, "that, as the opposition advances, in particular in Damascus, that regime might very well consider the use of chemical weapons."

The U.S. and others have warned of unspecified consequences if such weapons are used. On Thursday, Syria's Deputy Foreign Minister
Faisal Mekdad
accused the U.S. and Europe of using the issue of chemical weapons to justify a future military intervention against Syria, the AP reported. He warned that any such intervention would be "catastrophic."

The expected deployment of six Patriot batteries to Turkey followed comments by NATO diplomats in recent days that there would be significant gaps in protection.
Ivo Daalder,
U.S. ambassador to NATO, said Thursday the defense of the Turkish population was one of three reasons to send the Patriots to Turkey.

The purpose "first and most important was to reassure the Turks that in case of threats to their security…we have their back," Mr. Daalder said in an interview. The decision also sent a message of deterrence to Syria, he said.

A Turkish Foreign Ministry official said the number of batteries "is a matter that's being talked about between Turkey's armed forces and NATO. It will be decided between them. Talks on this matter are ongoing."

Given their size—the most modern Patriots carry 16 missiles per launching station—the batteries may have to be shipped by sea. The first is likely to take several weeks to arrive, with others following later, diplomats and officials said.

"There's certainly a threat on the Syrian border. But I think the Patriot deployment is more of a symbolic step, as it doesn't totally seal the border. Rather, it serves to intimidate and warn Syria, while also putting on a show to illustrate that NATO is a fully functioning alliance at a time when the organization's existence is being questioned," said
Salih Akyurek,
a former army colonel and researcher at the Wise Men Center for Strategic Studies in Ankara.

—Emre Peker in Istanbul, William Boston in Berlin and Jay Solomon in Washington contributed to this article.

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